1. Field of the Invention
The invention concerns an apparatus for withdrawing a liquid from a closed container. The container is provided with a withdrawal connection portion through which the liquid is taken from the container and passed for further use thereof. The container is in a fluctuating position in space if it is part of a portable piece of equipment.
The invention aims to make it possible to take a liquid from a closed container when the container is in any position in space so that the liquid withdrawn from the container can be used in the appropriate fashion and in a trouble-free manner.
2. Related Art
It is known for a liquid to be discharged downwardly from a rigid container through a discharge connection portion or to be withdrawn upwardly or laterally by means of a tube or hose which projects into the container. The discharged flow of liquid is bubble-free and uninterrupted as long as the liquid completely covers the discharge connection portion or as long as the end of the tube completely dips into the liquid. Those conditions can be easily observed when dealing with a container which is in a fixed position in space. The liquid in the container can be virtually completely withdrawn therefrom.
In portable pieces of equipment on the other hand a rigid liquid container can adopt any position in space. As long as one of the conditions specified for a container involving a fixed position in space is met, a bubble-free and uninterrupted flow of liquid can also be taken from a container whose position in space fluctuates. It is however not possible for the liquid in the container to be completely withdrawn therefrom.
It is further known to dispose in a rigid container a foil bag which contains the liquid and which collapses to the extent that liquid is taken from the foil bag (collapsible bag). Experience has shown that the liquid can no longer be withdrawn from the bag as soon as the foil comes to bear against the discharge connection or the end of the tube or hose. Experience has shown that this can occur before the foil bag is empty.
Accordingly an object of the invention is to provide an apparatus with which a liquid can be almost completely withdrawn from a closed container in a trouble-free manner, the container being provided with a withdrawal connection portion, containing a liquid and involving a position that fluctuates in space.